interface to network_methods table

[plcapi.git] / PLC / NetworkMethods.py

diff --git a/PLC/NetworkMethods.py b/PLC/NetworkMethods.py
new file mode 100644 (file)
index 0000000..e141429
--- /dev/null
+++ b/PLC/NetworkMethods.py
@@ -0,0 +1,73 @@
+#
+# Functions for interacting with the network_methods table in the database
+#
+# Mark Huang <mlhuang@cs.princeton.edu>
+# Copyright (C) 2006 The Trustees of Princeton University
+#
+# $Id: NetworkMethods.py,v 1.2 2006/10/06 18:19:41 mlhuang Exp $
+#
+
+from PLC.Faults import *
+from PLC.Parameter import Parameter
+from PLC.Table import Row, Table
+
+class NetworkMethod(Row):
+    """
+    Representation of a row in the network_methods table. To use,
+    instantiate with a dict of values.
+    """
+
+    table_name = 'network_methods'
+    primary_key = 'method'
+    fields = {
+        'method': Parameter(str, "Network method", max = 20),
+        }
+
+    def __init__(self, api, fields = {}):
+        Row.__init__(self, fields)
+        self.api = api
+
+    def validate_method(self, name):
+       # Remove leading and trailing spaces
+       name = name.strip()
+
+       # Make sure name is not blank after we removed the spaces
+        if not name:
+            raise PLCInvalidArgument, "Network method must be specified"
+       
+       # Make sure network method does not alredy exist
+       conflicts = NetworkMethods(self.api, [name])
+        if conflicts:
+            raise PLCInvalidArgument, "Network method name already in use"
+
+       return name
+
+    def delete(self, commit = True):
+        assert 'method' in self
+
+        # Clean up miscellaneous join tables
+        for table in ['nodenetworks', 'network_methods']:
+            self.api.db.do("DELETE FROM " + table + \
+                           " WHERE method = %(method)s",
+                           self)
+
+        if commit:
+            self.api.db.commit()
+        
+class NetworkMethods(Table):
+    """
+    Representation of the network_methods table in the database.
+    """
+
+    def __init__(self, api, names = None):
+        sql = "SELECT %s FROM network_methods" % \
+              ", ".join(NetworkMethod.fields)
+        
+        if names:
+            # Separate the list into integers and strings
+            sql += " WHERE method IN (%s)" % ", ".join(api.db.quote(names))
+
+        rows = api.db.selectall(sql)
+
+        for row in rows:
+            self[row['method']] = NetworkMethod(api, row)